Introduce finalizerProbe for the pods like we have livenessProbe

[bitsmaestro]

Enhancement Description

Requirement: while deleting a pod API server is not sure if anything on that pod is running or not. May be pod is still processing response for some rest call and we may loose it.

Enhancement: So suggestion is introduce an finalizerProbe which when curled should return if Pod is ready to die or not.
this should only be used when we get some external delete with force option, all other deletion scenarios should not care about finalizerProbe

finalizerProbe should return 500 if not ready to be deleted & 200 when ready to be deleted

Application inside the pod should ensure the logic to return return 500 or 200 as per the business
that new request is not accepted once a finalizerProbe is called or metadata.deletionTimestamp is added to the pod.

• One-line enhancement description (can be used as a release note): Introduce finalizerProbe for the pods like we have livenessProbe
• Kubernetes Enhancement Proposal:
• Discussion Link:
• Primary contact (assignee):
• Responsible SIGs: app
• Enhancement target (which target equals to which milestone):
  • Alpha release target (x.y):
  • Beta release target (x.y):
  • Stable release target (x.y):
• Alpha
  • KEP (k/enhancements) update PR(s):
  • Code (k/k) update PR(s):
  • Docs (k/website) update PR(s):

Please keep this description up to date. This will help the Enhancement Team to track the evolution of the enhancement efficiently.

[bitsmaestro]

/sig app

[k8s-ci-robot]

@bitsmaestro: The label(s) sig/app cannot be applied, because the repository doesn't have them.

In response to this:

/sig app

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[bitsmaestro]

/sig app

[k8s-ci-robot]

@bitsmaestro: The label(s) sig/app cannot be applied, because the repository doesn't have them.

In response to this:

/sig app

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[bitsmaestro]

/sig apps

[bitsmaestro]

Like HTTP we can implement similar concept for TCP probes and GRPC Health Checking Protocol also
error returned by finalizerProbe we dont delete the pod , success we delete the pod
it will be amalgamation of finalizers & probes concept